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The Duckworth–Lewis method (often written as D/L method) is a mathematical formulation designed to calculate the target score for the team batting second in a limited overs cricket match interrupted by weather or other circumstances. It is generally accepted to be the most accurate method of setting a target score. The D/L method was devised by two English statisticians, Frank Duckworth and Tony Lewis. The basic principle is that each team in a limited-overs match has two resources available with which to score runs: wickets remaining, and overs to play. Where overs are lost, setting an adjusted target for the team batting second is not as simple as reducing the run target proportionally to the loss in overs, because a team with ten wickets in hand and 25 overs to bat can be expected to play more aggressively than if they had ten wickets and a full 50 overs, for example, and can consequently achieve a higher run rate. The Duckworth–Lewis method is an attempt to set a statistically fair target for the second team's innings, based on the score achieved by the first team, taking their wickets lost and overs played into account. In November 2014, the Duckworth–Lewis method was renamed the Duckworth-Lewis-Stern (or D/L/S) method. ==Calculation summary== In the version of D/L most commonly in use in international and first class matches (the 'Professional Edition'), the target for the team batting second ('Team 2') is adjusted up or down from the total the team batting first ('Team 1') scored, in proportion to the two teams' resources (combination of overs and wickets available), i.e. . If, as usually occurs, this 'par score' is a non-integer number of runs, then Team 2's target to win is this number rounded up to the next integer, and the score to tie (also called the par score), is this number rounded down to the preceding integer. For example, if a rain delay means that Team 2 only has 90% of the resources that were available to Team 1, and Team 1 scored 254, then 254 x 90% = 228.6, so Team 2's target is 229, and the score to tie is 228. The actual resource values used in the Professional Edition are not publicly available,〔(espncricinfo D/L FAQ's Q15 )〕 so a computer must be used which has the software loaded. If it's a 50-over match and Team 1 completed its innings uninterrupted, then they had 100% resource available to them, so the formula simplifies to: . 抄文引用元・出典: フリー百科事典『 ウィキペディア（Wikipedia）』 ■ウィキペディアで「Duckworth–Lewis method」の詳細全文を読む スポンサード リンク
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